Platform (Core) Synopsis

Title

The Chronic kidney disease Adaptive Platform Trial Investigating Various Agents for Therapeutic Effect

Short title​

The CAPTIVATE Trial

Study phase

III

Trial registration

ClinicalTrials.gov Identifier: NCT06058585

Clinical Trials Registry – India (CTRI) Number: CTRI/2024/08/072628

Funding

National Health and Medical Research Council (Australia)

Study design

Adaptive, platform, randomised controlled trial

Primary objective

To determine investigational agents or combinations of agents that reduce the rate of eGFR decline (slow progression of CKD), compared to placebo, in patients with chronic kidney disease receiving standard of care therapy

Inclusion criteria

Potential participants must satisfy all of the following:

  1. Age ≥ 18 years
  2. Known chronic kidney disease from any cause (eGFR ≥25 mL/min/1.73m2)
  3. Currently receiving standard of care treatment according to treating physician
  4. Eligible for randomisation in at least one recruiting domain-specific appendix
  5. Participant and treating physician are willing and able to perform trial procedures

Exclusion criteria

Potential participants must have none of the following:

  1. Currently receiving maintenance dialysis
  2. Planned to commence kidney replacement therapy or kidney transplant surgery in next 6 months
  3. Life expectancy less than 6 months

Number of participants

Each intervention will have a maximum sample size specified within the associated domain-specific appendix (DSA).  The default sample size is 500 participants per intervention, which provides approximately 90% power to detect a 1.3 mL/min/1.73m2/year improvement in eGFR slope. The total sample size of a domain is obtained by summing up the individual interventions; a domain with a single intervention and a control will have a maximum sample size of approximately 1,000 participants. The final sample size will depend on the simulations conducted prior to the DSA implantation.

Treatment description

Unless specified within the relevant DSA, participants will be randomised to receive one intervention within each DSA. 

Primary outcome measure

eGFR slope calculated using eGFR values from randomisation to week 108

Secondary efficacy outcomes

  1. Change in albuminuria as measured by uACR (or uPCR if uACR unavailable) between randomisation and 24 weeks, measured as a continuous variable
  2. Composite outcome of proportion of participants experiencing a 40% eGFR decline between randomisation and 108 weeks, and proportion of participants developing kidney failure (defined as eGFR <15 mL/min/1.73m2 or chronic kidney replacement therapy start) at 108 weeks
  3. Time to a composite outcome of ≥40% eGFR decline from randomisation or kidney failure
  4. All-cause mortality at 108 weeks
  5. Proportion of participants experiencing one or more cardiovascular events (cardiovascular death, hospitalised heart failure, myocardial infarction, stroke) between randomisation and 108 weeks
  6. Time to first occurrence of a cardiovascular event
  7. Safety and tolerability of treatment
  8. Change in quality of life measured using the Quality of Life Impact Survey for Kidney Disease (QDIS-CKD) at 6-monthly intervals from randomisation to week 108

Tertiary efficacy outcomes

  1. All-cause mortality assessed at 5 years and at subsequent 5-year intervals
  2. Proportion of participants who have developed kidney failure assessed at 5 years and at subsequent 5-year intervals, as defined by requirement for chronic kidney replacement therapy or kidney transplant surgery